I have been having a few issues with my Mac and Apple support suggested I set up a new Mountain Lion Partition on my hard drive to test things out. Doing so has made my Windows 8 bootcamp partition unusable. I can see the bootcamp partition in finder, but the drive doesn't show up as a bootable option when starting the machine, so I can't use it. I originally purchased and installed it through a download upgrade. I have the product key but I do not have an ISO file or physical DVD. Is there any way to reinstall Windows 8 now or am I going to have to buy it again?